• Journal of Korean Vacuum Science & Technology
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• 제4권1호
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• pp.11-17
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• 2000

The low temperature electron mobilities were investigated in Si/$Si_{1-x}Ge_{x}$ modulation Doped (MOD) quantum well structure with thermally grown oxide. N-type Si/$Si_{1-x}Ge_{x}$ structures were fabricated by a gas source MBE. Thermal oxidation was carried out in a dry $O_2$ atmosphere at $700^{\circ}C$ for 7 hours. Electron mobilities were measured by a Hall effect and a magnetoresistant effect at low temperatures down to 0.4 K. Pronounced Shubnikov-de Haas (SdH) oscillations were observed at a low temperature showing two dimensional electron gases (2 DEG) in a tensile strained Si quantum well. The electron sheet density ($n_{s}$) of 1.5${\times}$$10^{12}$[$cm^{-2}$] and corresponding electron mobility of 14200 [$cm^2$$V^{-1}$$s^{-1}$] were obtained at low temperature of 0.4 K from Si/$Si_{1-x}Ge_{x}$ MOD quantum well structure with thermally grown oxide.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.142-143
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• 2006

Organic thin film transistors(OTFTs) were simulated by a SPICE model adopted in the amorphous TFTs(a-Si:H TFTs). The gate voltage-dependent mobilities were assumed to fit the representative current-voltage characteristics. The optimal fitting procedures were suggested to compare the experimental data with the mathematical expressions used in the amorphous TFTs. Each SPICE parameter explains the gate dependent mobilities in OTFTs which might originate from the influence of the hopping conduction.

• Coupled systems mechanics
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• 제6권1호
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• pp.75-96
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• 2017

As electron donor/acceptor materials for organic photovoltaic cells, small-molecules donors/acceptor are attracting more and more attention. In this work, we investigated the electronic structures, electrochemical properties, and charge carrier transport properties of four recently-synthesized small-molecule donors/acceptor, namely, DPDCPB (A), DPDCTB (B), DTDCPB (A1), and DTDCTB (B1), by a series of ab initio calculations. The calculations look into the electronic structure of singly oxidized and reduced molecules, the first anodic and cathodic potentials, and the electrochemical gaps. Results of our calculations were in accord with those from experiments. Using Marcus theory, we also computed the reorganization energies of hole/electron hoppings, as well as hole/electron transfer integrals of multiple possible molecular dimer configurations. Our calculations indicated that the electron/hole transport properties are very sensitive to the relative separations/orientations between neighboring molecules. Due to high reorganization energies for electron hopping, the hole mobilities in the molecular crystals are at least an order of magnitude higher than the electron mobilities.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.391.2-391.2
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• 2014

Solution-processible hybrid bipolar field effect transistors (HBFETs) with balanced hole and electron mobilities were fabricated using a combination of the organic p-type poly (3-hexylthiophene) (P3HT) layer and inorganic n-type ZnO material. The hole and electron mobilities were first optimized in single layer devices by using acetonitrile as a solvent additive to process the P3HT and annealing to process the ZnO layer. The highest hole mobility of the P3HT-only-devices with 5% acetonitrile was 0.15 cm2V-1s-1, while the largest electron mobility was observed in the ZnO-only-devices annealed at $200^{\circ}C$ and found to be $7.2{\times}10-2cm2V-1s-1$. The inorganic-organic HBFETs consisting of P3HT with 5% acetonitrile and ZnO layer annealed at $200^{\circ}C$ exhibited balanced hole and electron mobilities of $4.0{\times}10-2$ and $3.9{\times}10-2cm2V-1s-1$, respectively. The effect on surface morphology and crystallinity by adding acetonitrile and thermal annealing were investigated through X-ray diffraction and atomic force microscopy (AFM). Our findings indicate that techniques demonstrated herein are of great utility in improving the performance of inorganic-organic hybrid devices

• Transactions on Electrical and Electronic Materials
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• 제4권6호
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• pp.9-12
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• 2003

The electrical properties of stabilized amorphous selenium typical of the material used in direct conversion x-ray imaging devices are reported. Carrier mobility was measured using time-of-flight (TOF) measurements to investigate the transport properties of holes and electrons in stabilized a-Se film. A laser beam with pulse duration of 5 ns and wavelength of 350nm was illuminated on the surface of a-Se with thickness of 400 $\mu\textrm{m}$. The photo induced signals of a-Se film as a function of time were measured. The measured transit times of hole and electron were about 8.73${\mu}\textrm{s}$ and 229.17${\mu}\textrm{s}$, respectively. The hole and electron drift mobilities decreases with increase of electric field up to 4V/$\mu\textrm{m}$. Above 4V/$\mu\textrm{m}$, the measured drift mobilities exhibited no observable dependence with respect to electric field. The experimental results showed that the hole and electron drifting mobility were 0.04584 $\textrm{cm}^2$ V$\^$-1/s$\^$-1/ sand 0.00174 $\textrm{cm}^2$V$\^$-1/s$\^$-1/ at 10 V/$\mu\textrm{m}$.

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 창립 20주년기념 특별학술발표회
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• pp.276-277
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• 2009

• 한국컴퓨터정보학회논문지
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• 제10권2호
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• pp.133-141
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• 2005

무선 이동 통신망에서 위치관리에 대한 성능분석을 위해서 사용자의 이동 패턴의 모의실험 방안에 대한 연구가 요구되고 있다. 이러한 목적에 따라 본 논문은 무선 이동 망에서의 이동패턴을 갖는 사용자의 이동성 모델을 제안한다. 이동 사용자들은 임의적으로 움직이기도 하지만 특정 시간대에 규칙적인 이동을 반복하는 특성도 함께 가지고 있다. 따라서 제안된 모델은 사용자의 시간에 연관된 이동을 묘사하도록 구성하였다. 이 모델은 지점 이동, 타임 슬롯에 대한 이동확률, 이동에 대한 지형적 경로 등으로 구성된다. 또한 임의적인 이동과 규칙적인 이동 특성이 혼합된 경우에 대한 모의실험 방안도 함께 제안된다. 모의실험 결과는 의도했던 이동패턴을 갖는 이동 시나리오를 생성할 수 있음을 보여준다.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2655-2660
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• 2009

A breed of cattle, i.e., Korean cattle (Hanwoo), was identified based on the DNA mobilities of their microsatellites (MSs) by capillary gel electrophoresis (CGE) with a laser-induced fluorescence (LIF) detector. The MS markers were used for the accurate identification of species-specific genes. The DNA mobilities of the MS markers of Hanwoo and Holstein were measured using a CGE system with a fused-silica capillary (inner diameter of 75 ${\mu}m$, outer diameter of 365 ${\mu}m$, and total length of 50 cm). The capillary was dynamically coated with 1.0% (w/v) polyvinylpyrrolidone ($M_r$ = 1,000,000) and then filled with a mixture of 1.3% (w/v) poly(ethylene oxide) ($M_r$ = 600,000) and 1.9% (w/v) poly(ethylene oxide) (Mr = 8,000,000) as a sieving gel matrix. The species-specific genes of Hanwoo and Holstein were clearly distinguished within 33 min. This CGE assay technique is expected to be a useful analytical method for the fast and accurate identification of breeds of cattle.

• 한국멀티미디어학회논문지
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• 제24권8호
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• pp.1138-1148
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• 2021

In this study, we developed a 'shared-use mobility'-mounted local particulate matter monitoring terminal technology to measure the actual particulate matter concentration around me. As a mobile terminal device in the form of an IoT sensor platform, it is designed to be separated into a control module and a sensor module to minimize interference between sensors and to consider the optimal observation position of each sensor. As a result of the field test, it was confirmed that particulate matter was locally different depending on time and space even within the same area. In addition, it was confirmed that the concentration of particulate matter in the relevant section differed by up to 100 times compared to the surrounding area due to specific sources of particulate matter such as unpaved roads. In addition, we positively reviewed the applicability of the service in the real-time metaverse environment using this result. Through technological advancement and application of multiple shared-use mobilities, we expect to be able to provide new services for practical smart city air environment monitoring, such as localized particulate matter information, air pollution event information, and identification of causes of particulate matter.

• 한국식품영양학회지
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• 제1권1호
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• pp.25-32
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• 1988

Properties of purified isocitrate lyase from Saccharomycopsis lipolytica ATCC 44601 and MX9-11RX8 temperature-sensitive mutant were investigated. Purified isocitrate lyase from temperature-sensitive mutant was indistinguishable from the wild type enzyme with respect to the isoelectric pH(5.3), the thermostability and Km value for threo-Ds-Isocitrate(about 0.2 mM). When isocitrate lyase induced by acetate minimal medium at 33$^{\circ}C$, MX9-11RX8 mutant did not express enzyme activity but did synthesize polypeptide chain whose electrophoretic mobilities were equal to those of the purified enzymes.